1. Field of the Invention
This invention relates to an image forming apparatus and method of forming an image on a transfer medium, and a method and apparatus for image forming using the transfer medium.
2. Discussion of the Background
A method of image forming with an image transfer paper is known as a method of forming an image on a ceramic product, enamel product or glass product.
FIGS. 7A-7F show a method of image forming with an image transfer paper. In FIG. 7A, first an image is formed on an image transfer paper 900. By the following steps, the image on the transfer paper 900 is transferred to a ceramic product 905. The image transfer paper 900 includes a base paper 901 and a water-soluble paste layer 902 formed on the base paper 901.
As shown in FIG. 7B, in a first step, an ink image 903 is printed on the image transfer paper 900 by a screen printing method. Next, as shown in FIG. 7C, resins are provided on the water-soluble paste layer 902 and the printed image 903, and thus a resin layer 904 is formed, whereby an image transfer paper is fabricated.
In a next step as shown in FIG. 7D, the thus fabricated image transfer paper is inserted into water. The water-soluble paste layer 902 is thereby dissolved in the water, so that the base paper 901 is peeled off, whereby a separate resin layer 904 which bears an image 903 is obtained.
In a next step as shown in FIG. 7E, the thus obtained separated resin layer 904 is applied to the surface of a ceramic product 905. Next, the ceramic product 905 with the resin layer 904 is burned, whereby an image bearing ceramic product can be obtained, as shown in FIG. 7F.
In this method, an image is printed by a screen printing method. In a screen printing, a printing plate is required to be made. Since a basic printing mode of the screen printing is multi-color printing, 10 or more kinds of printing plates are usually required to obtain colorful images. Therefore, the cost for making such printing plates is high. Accordingly, the screen printing method is only used for manufacturing a small number of products.
Japanese Laid-Open Applications 4-135798 and 7-199540 propose a method of solving the above-mentioned problem in the screen printing method. As disclosed in these applications, a toner image is formed on a transfer paper 900 by a dry type copying machine, whereby a toner image bearing image transfer paper is prepared. The thus prepared toner image bearing a resin layer 904 is applied to the surface of the ceramic product 905. Then, the ceramic product 905 with the resin layer 904 is burned, whereby an image bearing ceramic product can be obtained.
This method, however, has a problem. A typical dry type copying machine is made for printing an image on white paper as a recording paper. Further, the toner which forms an image has some translucence. Therefore, in a typical dry type copying machine, a density of each color toner is made based on a decision of printing on white paper and the toner has some translucence. Moreover, a white color and near white color in a forming image is made by using the white color in a recording paper.
However, in the above method of an image forming on a ceramic product using an image transfer paper, because a color of a surface of many ceramic products is not white, an expected color cannot be obtained. This problem occurs in the case of not only forming an image on a ceramic product but also in forming an image on clothing, for example, a T-shirt.